Lithium‐ion batteries (LIBs) have been occupying the dominant position in energy storage devices. Over the past 30 years, silicon (Si)‐based materials are the most promising alternatives for graphite as LIB anodes due to their high theoretical capacities and low operating voltages. Nevertheless, their extensive volume changes in battery operation causes the structural collapse of Si‐based electrodes, as well as severe side reactions. In this review, the preparation methods and structure optimizations of Si‐based materials are highlighted, as well as their applications in half and full cells. Meanwhile, the developments of promising electrolytes, binders and separators that match Si‐based electrodes in half and full cells have made great progress. Pre‐lithiation technology has been introduced to compensate for irreversible Li+ consumption during battery operation, thereby improving the energy densities and lifetime of Si‐based full cells. More importantly, almost all related mechanisms of Si‐based electrodes in half and full cells are summarized in detail. It is expected to provide a comprehensive insight on how to develop high‐performance Si‐based full cells. The work can help us understand what happens during the lithiation process, the primary causes of Si‐based half and full cells failure, and strategies to overcome these challenges.

Co9S8-based materials have attracted tremendous attention owing to their unique physical properties, which are widely adopted as electrocatalysts in hydrogen- and oxygen-related electrocatalysis.

Si-based electrodes offer exceptionally high capacity and energy density for lithium-ion batteries (LIBs),but suffer from poor structural stability and electrical conductivity that hamper their practical applications. To tackle these obstacles, we design a C/polymer bilayer coating deposited on Si-SiO x microparticles. The inner C coating is used to improve electrical conductivity. The outer C-nanoparticle-reinforced polypyrrole (CNP-PPy) is a polymer matrix composite that can minimize the volumetric expansion of Si-SiO x and enhance its structural stability during battery operation. Electrodes made of such robust Si-SiO x @C/CNP-PPy microparticles exhibit excellent cycling performance: 83% capacity retention (794 mAh g–1) at a 2 C rate after more than 900 cycles for a coin-type half cell, and 80% capacity retention (with initial energy density of 308 Wh kg–1) after over 1100 cycles for a pouch-type full cell. By comparing the samples with different coatings, an in-depth understanding of the performance enhancement is achieved, i.e., the C/CNP-PPy with cross-link bondings formed in the bilayer coating plays a key role for the improved structural stability. Moreover, a full battery using the Si-SiO x @C/CNP-PPy electrode successfully drives a car model, demonstrating a bright application prospect of the C/polymer bilayer coating strategy to make future commercial LIBs with high stability and energy density.

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Exploration of efficient strategies for highly capacitive electrodes is of great significance for the development of advanced energy devices. Herein, we propose a novel method for the preparation of a hierarchical porous carbon material derived from longan pulp biomass for application in supercapacitors. First, a precursor of the two‐dimensional graphitized carbon with uniform carbon spheres is self‐assembled via a hydrothermal method with a post‐calcination process. After that, the longan pulp hierarchical porous carbon with inner pores is achieved through an embedding method with a mixture of precursor, KOH and KCl at high‐pressure and appropriate annealing temperature by self‐sacrificial means. The rich mesopores inside the sheet of LHPC‐3 demonstrate a more conducive strategy to create holes inside the materials, which is beneficial for electrical double‐layer capacitance. As a result, the LHPC‐3 is characterized with a high specific surface area of 1678 m2 g−1 and an abundance of meso‐/micropores, which facilitate the electrolyte penetration and mass transfer rates. Accordingly, LHPC‐3 exhibits an excellent specific capacitance of 380 and 153 F g−1 at 0.5 A g−1 in three‐electrode and symmetric supercapacitor systems, respectively. The new synthesis strategy is more conducive to the internal pore formation of carbon materials and has the potential to be widely applied to the synthesis of other electrochemical materials.